py38 unit test failures

[Corey Bryant]

murano has some py38 unit test failures. This can be tested with python 3.8 on ubuntu bionic. basepython may need to be updated to point directly to python3.8 in tox.ini.

[Corey Bryant (corey.bryant)]

The following unit tests are failing for tox -e py38. This can be tested on ubuntu bionic.

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FAIL: murano.tests.unit.common.test_wsgi.TestXMLDictSerializer.test_XML_Dict_Serializer_create_link_nodes
murano.tests.unit.common.test_wsgi.TestXMLDictSerializer.test_XML_Dict_Serializer_create_link_nodes
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testtools.testresult.real._StringException: Traceback (most recent call last):
  File "/<<PKGBUILDDIR>>/murano/tests/unit/common/test_wsgi.py", line 375, in test_XML_Dict_Serializer_create_link_nodes
    self.assertEqual('<atom:link href="href" rel="rel" type="type"/>',
  File "/usr/lib/python3/dist-packages/testtools/testcase.py", line 411, in assertEqual
    self.assertThat(observed, matcher, message)
  File "/usr/lib/python3/dist-packages/testtools/testcase.py", line 498, in assertThat
    raise mismatch_error
testtools.matchers._impl.MismatchError: !=:
reference = '<atom:link href="href" rel="rel" type="type"/>'
actual = '<atom:link rel="rel" href="href" type="type"/>'

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FAIL: murano.tests.unit.engine.test_package_loader.TestCombinedPackageLoader.test_export_fixation_table
murano.tests.unit.engine.test_package_loader.TestCombinedPackageLoader.test_export_fixation_table
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testtools.testresult.real._StringException: pythonlogging:'murano': {{{Loaded package from path /<<PKGBUILDDIR>>/murano/tests/unit/engine/meta}}}

Traceback (most recent call last):
  File "/<<PKGBUILDDIR>>/murano/tests/unit/engine/test_package_loader.py", line 617, in test_export_fixation_table
    self.assertEqual(sorted(expected_table.items()),
  File "/usr/lib/python3/dist-packages/testtools/testcase.py", line 411, in assertEqual
    self.assertThat(observed, matcher, message)
  File "/usr/lib/python3/dist-packages/testtools/testcase.py", line 498, in assertThat
    raise mismatch_error
testtools.matchers._impl.MismatchError: !=:
reference = [('test_package_1', ['1.1.1']), ('test_package_2', ['2.2.2', '3.3.3'])]
actual = [('test_package_1', ['1.1.1']), ('test_package_2', ['3.3.3', '2.2.2'])]